chan_sip: fix Local From tag on outbound register regression

In ASTERISK-12117, an improvement to insure consistant local from tags
on outbound registrations resulted in an undesirable behavior - caused
by leftover unexpired sip_pvt dialogs (with the previous cseq number),
resulting in many uncessary REGISTER requests.  Instead of significant
rework of transmit_register(), this change deletes the dialogs after a
200 OK response indiciating a successful registration, keeping the old
dialogs from interfering with normal operation.

(closes issue ASTERISK-22946)
Reported by: Stephan Eisvogel
Review: https://reviewboard.asterisk.org/r/3109/



git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/1.8@405433 f38db490-d61c-443f-a65b-d21fe96a405b
chan_sip: No BYE message sent after INVITE with Replaces

Setting channel state DOWN is an unnecessary step that was
only being done in handle_invite_replaces().  This changes
that by removing the call and reducing locking.

(closes issue ASTERISK-23010)
Reported by: Ryan Tilton
Review: https://reviewboard.asterisk.org/r/3116/


git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/1.8@405486 f38db490-d61c-443f-a65b-d21fe96a405b